Preparation of biodegradable materials with high water proof quality by use of cornstarch as the matrix

摘要

Biodegradable materials with high water proof quality were made by use of cornstarch as the matrix. First, cornstarch was carboxymethylated with monochloro acetic acid. Then, the ethanol solution of denatured cornstarch was poured into the mold and pressed after drying over night. The water proof quality was given by mixing cornstarch with the more hydrophobic cornstarch (Zein) or coating Zein onthe surface of pressed sheet of cornstarch. The water proof quality was found to increase with the concentration of Zein. The mechanical strength of the pressed plate increased with the concentration of Zein. In order to improve the mechanical strength, the paper fiber was incorporated into the matrix cornstarch. It was found that the mechanical strength was strongly dependent on the added amount of paper fiber.